Question

In woody dicotyledons, the arrangement of vessels is either diffuse porous or ring porous. Based on these data, which one of the following statements is correct.

• A. Ring porous vessels are specialized and are used for
  conducting more water for a shorter period only, when
  tyloses occur early in the vessels
• B. Although diffuse porous vessels are not so specialized as
  ring porous vessels, they conduct more water at all
  periods and through new xylem vessels added gradually
  during development
• C. Diffuse porous vessels carry more water and also faster
  because of a greater number of small vessels having
  greater capillary force
• D. Ring porous vessels conduct more water as they are
  formed early during development, when the need for
  water is great

Answer 1

The correct option is D Ring porous vessels conduct more water as they are

formed early during development, when the need for
water is great

Ring porous vessel is specialized and used for conducting more water for a shorter period. Although diffuse-porous vessels are not as specialized as ring-porous vessels. Still, they conduct more water at all periods and through new xylem vessels added gradually during development. Diffuse porous vessels carry more water and also faster due to the greater number of small vessels having greater capillary force. Ring porous vessels conduct more water as they are formed early during the development when the need for water is great.

The correct answer is D.